As a regulatory requirement in virtually all jurisdictions that allow gaming, it is necessary to have a technique to authenticate that the software installed in a gaming machine is tested and approved. In the past, gaming manufacturers have generally used EPROM-based hardware platforms to store program code. As a result, a number of software authentication techniques have been accepted as standards throughout the gaming industry. Depending upon the preferences of the local regulatory agency, these techniques generally include either a Kobetron signature or a hash function based on the data stored in the EPROM device.
Authentication of software programs basically occurs using two different methods in the field, again determined by the local regulatory agency. In one method, each EPROM is authenticated by a gaming agent prior to being installed in a gaming machine that is to be brought up for play. The EPROMs may be shipped directly to the gaming agency for authentication prior to the install date of the machine, or may be authenticated on the casino floor as the software is being installed in the machine. In another method, authentication is conducted on a spot-check basis. A gaming agent periodically visits a casino and picks machines selectively or at random to remove the software components for authentication.
Jurisdictional requirements require that storage media containing code or data be authenticated at power-up, continuously or at a periodic rate, or upon occurrence of predetermined events, such as the opening any doors or panels of the gaming device that allows access to internal circuitry. The storage media may be comprised of erasable programmable read-only memory devices (EPROMs), electrically erasable programmable read-only memory devices (EEPROMs), PROMs, CompactFlash storage cards, hard disk drives, CD drives, or substantially any non-volatile memory and in some cases volatile memory (e.g., NVRAM, specialty mask semiconductors, battery backed RAM, SRAM, DRAM, etc.). The storage media comprises a memory device and the data stored thereon. Authentication of storage media is controlled by the gaming device's central processing unit (CPU). However, authentication by the CPU may take more than several minutes due to increasing complexity of the gaming device's software and thus the storage size of the media.
For example, in some gaming machines, the authentication and boot process may require up to or more than three (3) complete (or close to complete) read cycles of the storage media. The three read cycles are required to complete software authentication of the gaming program as a whole (the bits of data), the gaming program files individually, and to load the software in an executable memory. Consider a game machine that takes advantage of and uses a media device that is potentially alterable or rewritable throughout execution of the program. Such an alterable media device could be, for example, a CompactFlash storage card, EEPROM, ROM, hard drive, CD ROM, DRAM, SRAM, or other non-volatile memory device (or volatile memory device) that can store an executable software program, or parts thereof, required for the gaming operation. Referring to FIG. 2, a typical software authentication algorithm would involve first reading all the bits of information from the alterable media device in order to validate the entire software media image 20. If the software media image (all the bits of information in the storage media) is successfully validated 22, then the executable software program stored in the alterable media device is read in order to validate each file of the gaming software program at the file level 24. If time file level authentication is successful 26, the gaming software program is read a third time in order to load the gaming software program into an executable memory device 28 such as a DRAM or any other applicable volatile or non-volatile memory. Thus, in order to authenticate and load the gaming program, the gaming program is read, for example, three times. If the time it takes to read the gaming program is T, then, at a minimum, the time required to authenticate the gaming program and load the appropriate executable memory devices or storage media of a gaming machine is 3T. In practicality, regulators and gaming operators have expressed a desire to see the time required to authenticate the gaming program in certain commercial products with large storage media components reduced. Thus, there is a need for a system and/or method for speeding up the authentication process.